Reply:It really depends on what type of fence it is, how long
you wish it to last, what type of post(s) they are, and how tall and of what material the
fence/ gate is made of. Typically yes, fences should have posts which are cemented
in the ground. However cedar posts are an exception, temporary fences are typically
not cemented, and many chain link fences are installed uncemented and with post flanges/
anchors which serve a similar purpose.